(define eceval
  (make-machine
   '(exp env val proc argl continue unev)
   eceval-operations
  '(
;;SECTION 5.4.4
read-eval-print-loop
  (perform (op initialize-stack))
  (perform
   (op prompt-for-input) (const ";;; EC-Eval input:"))
  (assign exp (op read))
  (assign env (op get-global-environment))
  (assign continue (label print-result))
  (goto (label eval-dispatch))
print-result
;;**following instruction optional -- if use it, need monitored stack
  (perform (op print-stack-statistics))
  (perform
   (op announce-output) (const ";;; EC-Eval value:"))
  (perform (op user-print) (reg val))
  (goto (label read-eval-print-loop))

unknown-expression-type
  (assign val (const unknown-expression-type-error))
  (goto (label signal-error))

unknown-procedure-type
  (restore continue)
  (assign val (const unknown-procedure-type-error))
  (goto (label signal-error))

signal-error
  (perform (op user-print) (reg val))
  (goto (label read-eval-print-loop))

;;SECTION 5.4.1
eval-dispatch
  (test (op self-evaluating?) (reg exp))
  (branch (label ev-self-eval))
  (test (op variable?) (reg exp))
  (branch (label ev-variable))
  (test (op quoted?) (reg exp))
  (branch (label ev-quoted))
  (test (op assignment?) (reg exp))
  (branch (label ev-assignment))
  (test (op definition?) (reg exp))
  (branch (label ev-definition))
  (test (op if?) (reg exp))
  (branch (label ev-if))
  (test (op lambda?) (reg exp))
  (branch (label ev-lambda))
  (test (op begin?) (reg exp))
  (branch (label ev-begin))
  (test (op application?) (reg exp))
  (branch (label ev-application))
  (goto (label unknown-expression-type))

ev-self-eval
  (assign val (reg exp))
  (goto (reg continue))
ev-variable
  (assign val (op lookup-variable-value) (reg exp) (reg env))
  (goto (reg continue))
ev-quoted
  (assign val (op text-of-quotation) (reg exp))
  (goto (reg continue))
ev-lambda
  (assign unev (op lambda-parameters) (reg exp))
  (assign exp (op lambda-body) (reg exp))
  (assign val (op make-procedure)
              (reg unev) (reg exp) (reg env))
  (goto (reg continue))

ev-application
  (save continue)
  (save env)
  (assign unev (op operands) (reg exp))
  (save unev)
  (assign exp (op operator) (reg exp))
  (assign continue (label ev-appl-did-operator))
  (goto (label eval-dispatch))
ev-appl-did-operator
  (restore unev)
  (restore env)
  (assign argl (op empty-arglist))
  (assign proc (reg val))
  (test (op no-operands?) (reg unev))
  (branch (label apply-dispatch))
  (save proc)
ev-appl-operand-loop
  (save argl)
  (assign exp (op first-operand) (reg unev))
  (test (op last-operand?) (reg unev))
  (branch (label ev-appl-last-arg))
  (save env)
  (save unev)
  (assign continue (label ev-appl-accumulate-arg))
  (goto (label eval-dispatch))
ev-appl-accumulate-arg
  (restore unev)
  (restore env)
  (restore argl)
  (assign argl (op adjoin-arg) (reg val) (reg argl))
  (assign unev (op rest-operands) (reg unev))
  (goto (label ev-appl-operand-loop))
ev-appl-last-arg
  (assign continue (label ev-appl-accum-last-arg))
  (goto (label eval-dispatch))
ev-appl-accum-last-arg
  (restore argl)
  (assign argl (op adjoin-arg) (reg val) (reg argl))
  (restore proc)
  (goto (label apply-dispatch))
apply-dispatch
  (test (op primitive-procedure?) (reg proc))
  (branch (label primitive-apply))
  (test (op compound-procedure?) (reg proc))  
  (branch (label compound-apply))
  (goto (label unknown-procedure-type))

primitive-apply
  (assign val (op apply-primitive-procedure)
              (reg proc)
              (reg argl))
  (restore continue)
  (goto (reg continue))

compound-apply
  (assign unev (op procedure-parameters) (reg proc))
  (assign env (op procedure-environment) (reg proc))
  (assign env (op extend-environment)
              (reg unev) (reg argl) (reg env))
  (assign unev (op procedure-body) (reg proc))
  (goto (label ev-sequence))

;;;SECTION 5.4.2
ev-begin
  (assign unev (op begin-actions) (reg exp))
  (save continue)
  (goto (label ev-sequence))

;ev-sequence
;  (assign exp (op first-exp) (reg unev))
;  (test (op last-exp?) (reg unev))
;  (branch (label ev-sequence-last-exp))
;  (save unev)
;  (save env)
;  (assign continue (label ev-sequence-continue))
;  (goto (label eval-dispatch))
;ev-sequence-continue
;  (restore env)
;  (restore unev)
;  (assign unev (op rest-exps) (reg unev))
;  (goto (label ev-sequence))
;ev-sequence-last-exp
;  (restore continue)
;  (goto (label eval-dispatch))
;;;Plato: change here
ev-sequence
  (test (op no-more-exps?) (reg unev))
  (branch (label ev-sequence-end))
  (assign exp (op first-exp) (reg unev))
  (save unev)
  (save env)
  (assign continue (label ev-sequence-continue))
  (goto (label eval-dispatch))
ev-sequence-continue
  (restore env)
  (restore unev)
  (assign unev (op rest-exps) (reg unev))
  (goto (label ev-sequence))
ev-sequence-end
  (restore continue)
  (goto (reg continue))
					
;;;SECTION 5.4.3

ev-if
  (save exp)
  (save env)
  (save continue)
  (assign continue (label ev-if-decide))
  (assign exp (op if-predicate) (reg exp))
  (goto (label eval-dispatch))
ev-if-decide
  (restore continue)
  (restore env)
  (restore exp)
  (test (op true?) (reg val))
  (branch (label ev-if-consequent))
ev-if-alternative
  (assign exp (op if-alternative) (reg exp))
  (goto (label eval-dispatch))
ev-if-consequent
  (assign exp (op if-consequent) (reg exp))
  (goto (label eval-dispatch))

ev-assignment
  (assign unev (op assignment-variable) (reg exp))
  (save unev)
  (assign exp (op assignment-value) (reg exp))
  (save env)
  (save continue)
  (assign continue (label ev-assignment-1))
  (goto (label eval-dispatch))
ev-assignment-1
  (restore continue)
  (restore env)
  (restore unev)
  (perform
   (op set-variable-value!) (reg unev) (reg val) (reg env))
  (assign val (const ok))
  (goto (reg continue))

ev-definition
  (assign unev (op definition-variable) (reg exp))
  (save unev)
  (assign exp (op definition-value) (reg exp))
  (save env)
  (save continue)
  (assign continue (label ev-definition-1))
  (goto (label eval-dispatch))
ev-definition-1
  (restore continue)
  (restore env)
  (restore unev)
  (perform
   (op define-variable!) (reg unev) (reg val) (reg env))
  (assign val (const ok))
  (goto (reg continue))
   )))


;Value: eceval

(define the-global-environment (setup-environment))
;Value: "the-global-environment --> ((... #f #t ... ... ... ... ... ... ... ...))"

(start eceval)


;;; EC-Eval input:
(define (factorial n)
  (define (iter product counter)
    (if (> counter n)
	product
	(iter (* counter product)
	      
	      (+ counter 1))))
  (iter 1 1))

(total-pushes = 3 maximum-depth = 3)
;;; EC-Eval value:
ok

;;; EC-Eval input:
(factorial 1)

(total-pushes = 70 maximum-depth = 17)
;;; EC-Eval value:
1

;;; EC-Eval input:
(factorial 2)

(total-pushes = 107 maximum-depth = 20)
;;; EC-Eval value:
2

;;; EC-Eval input:
(factorial 3)

(total-pushes = 144 maximum-depth = 23)
;;; EC-Eval value:
6

;;; EC-Eval input:
(factorial 4)

(total-pushes = 181 maximum-depth = 26)
;;; EC-Eval value:
24

;;; EC-Eval input:
(factorial 5)

(total-pushes = 218 maximum-depth = 29)
;;; EC-Eval value:
120

;;; EC-Eval input:
(factorial 6)

(total-pushes = 255 maximum-depth = 32)
;;; EC-Eval value:
720

;;; EC-Eval input:
(define (factorial n)
  (if (= n 1)
      1
      (* (factorial (- n 1)) n)))

(total-pushes = 3 maximum-depth = 3)
;;; EC-Eval value:
ok

;;; EC-Eval input:
(factorial 1)

(total-pushes = 18 maximum-depth = 11)
;;; EC-Eval value:
1

;;; EC-Eval input:
(factorial 2)

(total-pushes = 52 maximum-depth = 19)
;;; EC-Eval value:
2

;;; EC-Eval input:
(factorial 3)

(total-pushes = 86 maximum-depth = 27)
;;; EC-Eval value:
6

;;; EC-Eval input:
(factorial 4)

(total-pushes = 120 maximum-depth = 35)
;;; EC-Eval value:
24

;;; EC-Eval input:
(factorial 5)

(total-pushes = 154 maximum-depth = 43)
;;; EC-Eval value:
120

;;; EC-Eval input:
(factorial 6)

(total-pushes = 188 maximum-depth = 51)
;;; EC-Eval value:
720

;;; EC-Eval input:

;                       Maximum depth Number of pushes
;Recursive factorial        8n+3         34n-16       
;Iterative factorial        3n+14        37n+33